I've done tons of unhemmed banners. As long as there's no heavy coverage that cause the vinyl to curl or you're using a vinyl that lays flat I think they look better than a taped hem that tends to pucker when rolled up.
In a lot of cases The customer doesn't even want grommets so I'll just pre-apply some banner hem tape to the backside that they can use to stick it to the wall with. I offer a lot of customers a smooth finish banner vinyl in place of
paper for presentation materials. They prefer something that doesn't kink as bad as
paper does when they're traveling and using the poster repeatedly. It just holds up to moderate abuse better than anything else.
